The degradation of catechins and other phenolics in green tea infusions were monitored using fast HPLC/MS separation. The final separation was performed within 2.5min using Ascentis Express C18 column (50mm×2.1mm i.d.) packed with 2μm porous shell particles. Degradation was studied in relation to the temperature of water (70, 80, 90°C) and the standing time of the infusion (up to 6h). Along with chromatographic separation, the antioxidant properties of the infusions were monitored using two spectrophotometric methods. During staying of green tea infusion, the degradation of some catechins probably to gallic acid was observed. Finally, the influence of tea bag storage on antioxidant properties of green tea was evaluated. Rapid degradation of antioxidants after 3weeks was observed. The principal component analysis, factor analysis and discriminant analysis were used for the statistical evaluation of obtained experimental data.
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http://dx.doi.org/10.1016/j.foodchem.2017.05.133 | DOI Listing |
The insecticide susceptibility of Waterhouse (Hemiptera: Miridae) is being evaluated using shoot and glass-vial assay as described by IRAC. However, the reliability of the assay depends on feeding preference and contact toxicity. Hence, the cocoa pod was used as a substrate to test the susceptibility of in comparison with existing methods.
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December 2024
Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham NH 03824.
Cancer is an extraordinarily complex illness, with many tumors ultimately developing resistance to the currently available therapeutics. This highlights a need for the discovery of new anticancer medicines. Natural products have been utilized for centuries by the indigenous people of Alaska for both spiritual and medicinal purposes and have traditionally been administered as medicine for a wide range of ailments from the common cold to cancer.
View Article and Find Full Text PDFChem Sci
January 2025
Chemistry and Physics of Materials Unit, School of Advanced Materials (SAMat), Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur Bangalore 560064 India https://www.jncasr.ac.in/faculty/tmaji.
Coordination-driven metallo-supramolecular polymers hold significant potential as highly efficient catalysts for photocatalytic CO reduction, owing to the covalent integration of the light harvesting unit, catalytic center and intrinsic hierarchical nanostructures. In this study, we present the synthesis, characterization, and gelation behaviour of a novel low molecular weight gelator (LMWG) integrating a benzo[1,2-:4,5-']dithiophene core with terpyridine (TPY) units alkyl amide chains (TPY-BDT). The two TPY ends of the TPY-BDT unit efficiently chelate with metal ions, enabling the formation of a metallo-supramolecular polymer that brings together the catalytic center and a photosensitizer in close proximity, maximizing catalytic efficiency for CO reduction.
View Article and Find Full Text PDFFront Nutr
January 2025
College of Tea and Food Science, Xinyang Normal University, Xinyang, China.
Tea flower, with characteristic flavor formed during blooming, are a significant tea resource. However, studies on the volatile compounds of tea flower and their aroma characteristics during flowering are scarce. In this study, the odor characteristics of tea flower during blooming were comprehensively investigated by GC-MS, PCA, ACI determination and sensory evaluation.
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January 2025
Department of Food Science and Engineering, Moutai Institute, Renhuai, 564502, People's Republic of China.
Hawk tea has received increasing attention for its unique flavor and potential health benefits, with antioxidant function being one of its significant bioactivities. However, the metabolic profiles, potential antioxidant components, and action mechanisms of different types of hawk tea are still unclear. In this study, the chemical components of five hawk teas were determined using untargeted metabolomics.
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